Qatar has declared the first secretary at the Russian embassy in Doha persona non grata and asked him to leave the country within 24 hours. The Qatari foreign ministry addressed an official memo Tuesday evening to the Russian embassy, noting that the first secretary Alexander Vitisov was considered persona non grata and should leave the state within 24 hours, an official source at the Qatari foreign ministry told Qatar News Agency (QNA) on Wednesday.

The source added that the memo also reiterated that the Russian government should honor its commitments according to the international law, governing diplomatic relations relevant to the issue of the Russian diplomat.

For its part, Russia confirmed Wednesday that Vitisov has already flown to Moscow.

Russian Ambassador in Doha Viktor Kudryavtsev told Itar-Tass that the first secretary of had been given permission to leave Doha as a result of the recent diplomatic efforts.

The diplomat has been in the Qatari capital since January. Another two Russian citizens who were detained together with the diplomat, remain in Qatari custody.

The Federal Security Service said in Moscow on Wednesday that the two Qatari citizens detained last month in the city, on suspicion of being involved in "illegal paramilitary groups," were released from custody on March 23 and left Russia.

Tension between Doha and Moscow has intensified as Qatar voiced suspicion of Russian involvement in the recent killing of a Chechen leader in Qatar.

Zelimkhan Yandarbiyev lived in Qatar since 2000 and Russian authorities pressed for his extradition on charges of "terrorism" and links to Osama bin Laden's al-Qaeda network. (Albawaba.com)